Research And Analysis On Fatigue Characteristics Of Multi-dimensional Robot Wire And Cable

Since the appearance of the mechanical arm,with the development of intelligence,the degrees of freedom are getting higher and higher meanwhile the range of application is getting much wider,which increases the demands on its components.Wires and cables as"vessels" and "nerves" of the mechanical arm,which require flexibility,excellent fatigue resistance,anti-electromagnetic interference,oil resistance,corrosion resistance,wear resistance,waterproofness,high or low temperature resistance,radiation resistance and a series of excellent properties.The mechanical arm with high degree of freedom and dimensions,in many uses,may use several dimensions at the same time,which would require the wires and the cables to have excellent bending resistant.Domestic research and development on cables used in mechanical arm were started relatively later than Japan,Europe and the United States.There is still a big gap in quality between the domestic cables and the imported ones.Since the big difference of the wire and cable USEs,the wire and cable manufacturers need to custom a torsion test equipment suitable for specific situations.But there are so many occasions,and it's unrealistic to custom all the torsion test equipment for all USEs.Therefore,whether it is possible to use soft wire to simulate the fatigue state of wire and cable after the bending torsion test is considered.Therefore,it is of great significance to carry out experimental research and simulation analysis of cable fatigue characteristics to ensure the safety of manipulator.Firstly,the stress and strain of wires and cables under torsion and the axial stress response of conductors are analyzed.It is known that the bending stress of the central conductor is the largest and the most prone to fatigue damage.However,a conductor without center strand is not round in actual production,which can lead to uneven insulation thickness and even insulation failure.Finally,a wire with 1+6 conductor structure is selected as the research object.Secondly,wire sample was manufactured according to UL 758,the twist parameter has confirmed base industry standard.Combined with the actual situation,2D torsion test has been applied.Meanwhile,DC resistance value at 25? of sample was monitored to verify the variation rule of DC resistance value can be used as a reliable evidence for confirming the progress of torsion test.Finally,the wire's 3D modeling is performed through SolidWorks.Finite element analysis software ANSYS was used to simulate the fatigue strength under the random load conditions.The study has resulted in different results for the equivalent stress distribution,total deformation,fatigue life,safety factor,rainflow matrix and relative damage distributionThe final result shows,that cable fatigue strength is low at the fixed end which mean the result of ANSYS software has the same develop tendency.The research results of this paper can provide technical support for the subsequent wire and cable bending and torsion tests,and also have important significance and practical value for the design of high-precision wires and cables that can withstand torsion and bending.